(1):

(n.) The act of incrusting, or the state of being incrusted.

(2):

(n.) A crust or hard coating of anything upon or within a body, as a deposit of lime, sediment, etc., from water on the inner surface of a steam boiler.

(3):

(n.) A covering or inlaying of marble, mosaic, etc., attached to the masonry by cramp irons or cement.

(4):

(n.) Anything inlaid or imbedded.